A review of Space Men, on PBS, turns up a new hero in pre-NASA space adventures.

Aside from documentaries by Ken and Ric Burns, my favorite PBS program is American Experience, the invariably well done series that covers slices of US history. So when I heard the network planned to run an episode on "pre-astronauts," people who pushed into the edge of space and tested human physiology in extreme environments before NASA rose to prominence, I was eager to watch.

Space Men premieres Tuesday at 9pm ET on PBS. It chronicles Project Manhigh and Project Excelsior, two initiatives in which explorers rose as high as 102,800 feet in helium-filled balloons to experience the frigid cold and near zero atmospheric pressure of such altitudes. In some ways these missions set the stage for Project Mercury, which would come shortly after, and they're worth remembering for their own sake.

While I was familiar with Project Excelsior and the daring high altitude jumps made by Col. Joseph Kittinger, I admit I never heard the name John Paul Stapp, who entered the Army Air Corps as a physician in 1944. He really stands out in this episode as an out-of-his-time man who foresaw that one day humans would fly into space.

Back in the 1940s there were many more questions than answers. How high was too high for humans? Was there a maximum speed the human body could tolerate? How would humans behave at high altitudes? Was there a limit to how far one could fall? Would cosmic rays in the upper atmosphere blind people? Stapp is perhaps most well known for his exploration of the question about g-forces, however: How much could the human body tolerate?

Stapp set about trying to conduct experiments to test how humans would react to such a harsh environment, and Space Men has tremendous footage of this aerospace pioneer strapping himself into a “rocket sled” and accelerating down a track before braking rapidly. Stapp did not believe in subjecting others to such harsh conditions without going first. He went through a series of increasingly harsh experiments in the 1950s until his last ride in the sled—when he reached a velocity of 632mph. At the time it was a land speed record, but Stapp's top velocity only lasted a few moments before he hit the brakes hard within seconds. He pulled 46.2G.

John Paul Stapp rides on an early version of his rocket sled at Edwards Air Force Base in California.

Wikimedia

Air Force portrait of John Paul Stapp.

Courtesy of Wilford Stapp

Time-sequence photos of Stapp on the rocket sled "Sonic Wind I" during a 421 mph-run in March 1954.

Wikimedia

Stapp experiences a microgravity experience during a parabolic flight.

Courtesy of Wilford Stapp

Joseph Kittinger sits in the gondola before rising to the stratosphere during Project Manhigh in June 1957.

Courtesy of Joseph Kittinger

Major David G. Simon, who set a new altitude record of 102,000 feet in a 32-hour balloon flight, near the peak of his climb to heights never before reached by a balloon in August 1957.

Courtesy of the National Museum of the United States Air Force

Joseph Kittinger suited up for Project Excelsior.

Courtesy of the National Museum of the United States Air Force

Kittinger jumps from his balloon gondola in 1960.

National Museum of the US Air Force

No human had ever come close to such extreme conditions then; none have come close since. Although Stapp lost his sight for a time after this final extreme run down the track, he eventually recovered. But as daring as Stapp's experiments were, the US Air Force failed to foresee the coming space race and didn’t see the value. Stapp had to constantly battle for funding.

Eventually, he found enough to conduct Project Manhigh, in which Kittinger flew to 96,784 feet in gondola in 1957. This was followed by other researchers into a realm above 99 percent of the Earth’s atmosphere. Shortly after Stapp and Kittinger's achievement, the Soviet Union launched Sputnik into space in October, 1957. And from the information Stapp had acquired, he helped NASA develop a regimen of tests that led to the selection of the Mercury 7 astronauts.

Stapp’s last major “space” initiative was Excelsior, in which the Air Force wanted to collect information about pilots bailing out from high-altitude jets. How high could a human survive a jump from? On August 16, 1960, they found out when Kittinger, a test pilot, climbed into the balloon, rose to the edge of space, and the leaped into the unknown. Some 13 minutes and 45 seconds later he landed safely.

“I was used to going up and flying in unusual situations, and this was an extension of that,” Kittinger told Ars in an interview. “I’d gone through this jump 1,000 times in my mind and worked to get ready for it for 1.5 years. So when it came time to jump I was ready to go, I had confidence in my team, and in my equipment. Gravity is a law, and I knew I was going to go down.”

Kittinger said he was glad to see that Space Men had put such a strong focus on Stapp, whom he regarded as a visionary who never got his due. “He was the bravest man I ever met in my life because that man knew exactly what was going to happen to himself before he undertook a sled run,” Kittinger said. The awe in his voice comes from a man who jumped from a balloon 102,800 feet above the Earth 55 years ago.

Watch a preview of Space Men.

The more I looked into Stapp’s background, the more I was impressed. Even as he exposed himself to violent crash simulations, he learned that more Air Force personnel were dying in automobile crashes than airplane crashes. Automobile safety, he realized, was a big problem.

In 1955, according to author Craig Ryan who has written about Stapp, the Air Force physician convened the first independent conference on automobile safety to prevent death and major injury from accidents. He testified before Congress multiple times and incurred the wrath of the Big Three automakers. Detroit fought hard, in fact, but in the end Detroit lost.

When President Lyndon Johnson signed the National Traffic and Motor Vehicle Safety Act into law in 1966, Stapp was there in the Rose Garden for the ceremony. He became the National Highway Traffic Safety Administration’s chief medical scientist. Two years later, seat belts became standard equipment in US automobiles. Humans, the successors to Stapp's earliest space men, landed on the Moon a year after that.

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